import fs from 'fs'; 
  
const readStream = fs.createReadStream('./aaa.txt', {  
    start: 8,  
    end: 22,  
    highWaterMark: 3  
});  
  
readStream.on('data', (data) => {  
    console.log(data.toString());  
    readStream.pause();  
    setTimeout(() => {  
        readStream.resume();  
    }, 2000);  
});  
  